In recent years the sport of Moto Cross competition has been gaining increasingly wide acceptance. In this sport, the bicycles are raced along a track full of obstacles which require the rider, among other things, to jump the bicycle over these obstacles. In order to maintain control of the bicycle during these jumps and while the bicycle is travelling over rough terrain, it is essential that the feet of the rider remain in contact with the bike pedal, otherwise, valuable time may be lost while the rider is trying to reposition his feet on the pedal. In addition, successful competition requires that power be transmitted from the bike rider to the pedal of the bike with maximum efficiency.
Heretofore efforts were made to provide bicycle shoes which were designed to hold the shoe in contact with the pedal. These efforts are exemplified by the patents to Haver, U.S. Pat. No. 4,188,737; Polsky, U.S. Pat. No. 3,952,428; McIntyre, U.S. Pat. No. 598,325; Rathbun, U.S. Pat. No. 589,443, and the French Pat. No 2,532,530 to Danielli and the French Pat. No. 2,301,193 to Soubirac.
These patents solved the problem of maintaining the bike shoe in contact with a bike pedal by forming a recess in the sole of the shoe for engaging at least a part of the bike pedal, or by installing a device on the sole of the shoe for attachment to the pedal. However, none of the prior art bike shoes were particularly suited for competitive Moto Cross competition and many were uncomfortable to walk on.
More importantly, prior art bike shoe designers did not consider the necessity of designing the bike shoe for holding the shoe in a stable position in contact with the pedal while the bicycle is riding over rough terrain during competition. In addition, the prior art bike shoe designers did not adequately consider the importance of designing the shoe to provide for the maximum transfer of power between the bike shoe and the pedal.
The patent to Haver U.S. Pat. No. 4,188,737 which superficially resembles Applicant's bike shoe has the advantage that it is reasonably comfortable to walk on and does not mar or scratch floor surfaces. Its disadvantage from the standpoint of Moto Cross competition is that it does not hold the bike shoe in a stable position in contact with the pedal and the location of the shoe with respect to the pedal does not provide for the maximum transfer of power.
The reason that the bike shoe shown in the Haver patent does not hold the bike shoe in a stable position over the pedal is that the walls of the Haver recess slope inwardly and upwardly. This arrangement permits the pedal to pivot inside the bike shoe recess. Consequently, during competition, while racing over rough terrain, the pedal can easily slip out of the recess so that time is lost while the rider is trying to reposition his feet on the pedal. This is admitted by Haver in his patent, when he states that his structure permits "easy disengagement of the pedal from the recess." This is the exact opposite of what is needed in competitive racing. Moreover, Haver does not locate his recess in alignment with the ball of the foot, which is also necessary for the maximum transfer of power.
The bike shoe described herein provides a stable relationship between the bike shoe and the pedal because the walls of the recess are perpendicular to the plane of the base of the recess and are spaced apart a distance generally equal to the width of the pedal to hold the pedal inside the recess. Consequently, the bike shoe cannot pivot inside the recess. With the recess in the shoe aligned with the ball of the foot, the foot does not exert any torque action on the pedal because the force from the foot is directed perpendicular to the surface of the pedal while the pedal is held parallel to the surface of the ground. This maximizes the transfer of power from the foot of the rider to the pedal of the bike. The reason is, if the center of the recess is located too far back from the center of the ball of the foot, the foot of the bike rider would have to be rotated upwardly in order to keep the pedal in the recess and if the center of the recess is located too far forward of the center of the ball of the foot, the foot would have to be rotated downward to keep the pedal in the recess. In either case, this would decrease power transmitted from the foot of the bike rider to the pedal of the bike.
What is needed therefore, and comprises an important object of this invention is to provide a bike shoe with a recess formed in the sole of the shoe which is sized to snugly embrace a bike pedal and which is located so when the rider wears the shoe, the center of the ball of the foot is aligned with the center of the recess.